Wilber was born in 1949 in Oklahoma City. In 1967 he enrolled as a pre-med student at Duke University.[3] He became inspired, like many of his generation, by Eastern literature, particularly the Tao Te Ching. He left Duke and enrolled at the University of Nebraska at Lincoln, but after a few years dropped out of university to devote all his time to studying his own curriculum and writing books.[4]

In 1973 Wilber completed his first book, The Spectrum of Consciousness,[7] in which he sought to integrate knowledge from disparate fields. After rejections by more than twenty publishers it was finally accepted in 1977 by Quest Books, and he spent a year giving lectures and workshops before going back to writing. He also helped to launch the journal ReVision in 1978.[8]

In 1982 New Science Library published his anthology The Holographic Paradigm and Other Paradoxes,[9] a collection of essays and interviews, including one by David Bohm. The essays, including one of his own, looked at how holography and the holographic paradigm relate to the fields of consciousness, mysticism, and science.

In 1983 Wilber married Terry "Treya" Killam who was shortly thereafter diagnosed with breast cancer. From 1984 until 1987, Wilber gave up most of his writing to care for her. Killam died in January 1989; their joint experience was recorded in the 1991 book Grace and Grit.

Subsequently, Wilber wrote Sex, Ecology, Spirituality (1995), the first volume of his Kosmos Trilogy. A Brief History of Everything (1996) was the popularised summary of Sex, Ecology, Spirituality in interview format. The Eye of Spirit (1997) was a compilation of articles he had written for the journal ReVision on the relationship between science and religion. Throughout 1997, he had kept journals of his personal experiences, which were published in 1999 as One Taste, a term for unitary consciousness. Over the next two years his publisher, Shambhala Publications, released eight re-edited volumes of his Collected Works. In 1999, he finished Integral Psychology and wrote A Theory of Everything (2000). In A Theory of Everything Wilber attempts to bridge business, politics, science and spirituality and show how they integrate with theories of developmental psychology, such as Spiral Dynamics. His novel, Boomeritis (2002), attempts to expose what he perceives as the egotism of the baby boom generation.

All Quadrants All Levels (AQAL), pronounced "ah-qwul", is the basic framework of integral theory. It models human knowledge and experience with a four-quadrant grid, along the axes of "interior-exterior" and "individual-collective". According to Wilber, it is a comprehensive approach to reality, a metatheory that attempts to explain how academic disciplines and every form of knowledge and experience fit together coherently.[2]

AQAL is based on four fundamental concepts and a rest-category: four quadrants, several levels and lines of development, several states of consciousness, and "types", topics which do not fit into these four concepts.[12] "Levels" are the stages of development, from pre-personal through personal to transpersonal. "Lines" of development are various domains which may progress unevenly through different stages .[note 1] "States" are states of consciousness; according to Wilber persons may have a temporal experience of a higher developmental stage.[note 2] "Types" is a rest-category, for phenomena which do not fit in the other four concepts.[13] In order for an account of the Kosmos to be complete, Wilber believes that it must include each of these five categories. For Wilber, only such an account can be accurately called "integral". In the essay, "Excerpt C: The Ways We Are in This Together", Wilber describes AQAL as "one suggested architecture of the Kosmos".[14]

The model's apex is formless awareness, "the simple feeling of being", which is equated with a range of "ultimates" from a variety of eastern traditions. This formless awareness transcends the phenomenal world, which is ultimately only an appearance of some transcendental reality. According to Wilber, the AQAL categories — quadrants, lines, levels, states, and types – describe the relative truth of the two truths doctrine of Buddhism. According to Wilber, none of them are true in an absolute sense. Only formless awareness, "the simple feeling of being", exists absolutely.[citation needed][note 3]

One of Wilber's main interests is in mapping what he calls the "neo-perennial philosophy", an integration of some of the views of mysticism typified by Aldous Huxley's The Perennial Philosophy with an account of cosmic evolution akin to that of the Indian mystic Sri Aurobindo. He rejects most of the tenets of Perennialism and the associated anti-evolutionary view of history as a regression from past ages or yugas.[15] Instead, he embraces a more traditionally Western notion of the great chain of being. As in the work of Jean Gebser, this great chain (or "nest") is ever-present while relatively unfolding throughout this material manifestation, although to Wilber "... the 'Great Nest' is actually just a vast morphogenetic field of potentials ..." In agreement with Mahayana Buddhism, and Advaita Vedanta, he believes that reality is ultimately a nondual union of emptiness and form, with form being innately subject to development over time.

Wilber believes that the mystical traditions of the world provide access to, and knowledge of, a transcendental reality which is perennial, being the same throughout all times and cultures. This proposition underlies the whole of his conceptual edifice, and is an unquestioned assumption.[note 4] Wilber juxtaposites this generalisation to plain materialism, presenting this as the main paradigma of regular science.[18][quote 1]

Wilber believes that many claims about non-rational states make a mistake he calls the pre/trans fallacy. According to Wilber, the non-rational stages of consciousness (what Wilber calls "pre-rational" and "trans-rational" stages) can be easily confused with one another. In Wilber's view, one can reduce trans-rational spiritual realization to pre-rational regression, or one can elevate pre-rational states to the trans-rational domain.[21] For example, Wilber claims that Freud and Jung commit this fallacy. Freud considered mystical realization to be a regression to infantile oceanic states. Wilber alleges that Freud thus commits a fallacy of reduction. Wilber thinks that Jung commits the converse form of the same mistake by considering pre-rational myths to reflect divine realizations. Likewise, pre-rational states may be misidentified as post-rational states.[22] Wilber characterizes himself as having fallen victim to the pre/trans fallacy in his early work.[23]

Wilber describes the current state of the "hard" sciences as limited to "narrow science", which only allows evidence from the lowest realm of consciousness, the sensorimotor (the five senses and their extensions). Wilber sees science in the broad sense as characterized by involving three steps:[24][25]

specifying an experiment,

performing the experiment and observing the results, and

checking the results with others who have competently performed the same experiment.

According to Wilber's theory, narrow science trumps narrow religion, but broad science trumps narrow science. That is, the natural sciences provide a more inclusive, accurate account of reality than any of the particular exoteric religious traditions. But an integral approach that uses intersubjectivity to evaluate both religious claims and scientific claims will give a more complete account of reality than narrow science.[citation needed]

In 2005, at the launch of the Integral Spiritual Center, a branch of the Integral Institute, Wilber presented a 118-page rough draft summary of his two forthcoming books.[28] The essay is entitled "What is Integral Spirituality?", and contains several new ideas, including Integral post-metaphysics and the Wilber-Combs lattice. In 2006, he published "Integral Spirituality", in which he elaborated on these ideas, as well as others such as Integral Methodological Pluralism and the developmental conveyor belt of religion.

The Wilber-Combs Lattice is a conceptual model of consciousness developed by Wilber and Allan Combs. It is a grid with sequential states of consciousness on the x axis (from left to right) and with developmental structures, or levels, of consciousness on the y axis (from bottom to top). This lattice illustrates how each structure of consciousness interprets experiences of different states of consciousness, including mystical states, in different ways.[citation needed]

Since then, Wilber has drawn back from public life, due to a severe illness.

Wilber attracted a lot of controversy from 2011 to the present day by supporting Marc Gafni. Gafni was accused in the media of sexually assaulting a minor.[29] Wilber has in fact publicly supported Gafni on his blog.[30][31] A petition begun by a group of Rabbis has called for Wilber to publicly dissociate from Gafni.

According to Frank Visser, Wilber's conception of four quadrants, or dimensions of existence is very similar to E. F. Schumacher's conception of four fields of knowledge.[37] Visser finds Wilber's conception of levels, as well as Wilber's critique of science as one-dimensional, to be very similar to that in Huston Smith's Forgotten Truth.[38] Visser also writes that the esoteric aspects of Wilber's theory are based on the philosophy of Sri Aurobindo as well as other theorists including Adi Da.[39]

Wilber has been categorized as New Age due to his emphasis on a transpersonal view[40] and, more recently, as a philosopher.[41]Publishers Weekly has called him "the Hegel of Eastern spirituality".[42]

Wilber is credited with broadening the appeal of a "perennial philosophy" to a much wider audience. Cultural figures as varied as Bill Clinton,[43]Al Gore, Deepak Chopra, Richard Rohr,[44] and musician Billy Corgan have mentioned his influence.[45] However, Wilber's approach has been criticized as excessively categorizing and objectifying, masculinist,[46][47] commercializing spirituality,[48] and denigrating of emotion.[49] Numerous critics cite problems with Wilber's interpretations and inaccurate citations of his wide ranging sources, as well as stylistic issues with gratuitous repetition, excessive book length, and hyperbole.[50]

Steve McIntosh praises Wilber's work but also argues that Wilber fails to distinguish "philosophy" from his own Vedantic and Buddhist religion.[51]Christopher Bache is complimentary of some aspects of Wilber's work, but calls Wilber's writing style glib.[52]

Psychiatrist Stanislav Grof has praised Wilber's knowledge and work in the highest terms;[53] however, Grof has criticized the omission of the pre- and peri-natal domains from Wilber's spectrum of consciousness, and Wilber's neglect of the psychological importance of biological birth and death.[54] Grof has described Wilber's writings as having an "often aggressive polemical style that includes strongly worded ad personam attacks and is not conducive to personal dialogue."[55] Wilber's response is that the world religious traditions do not attest to the importance that Grof assigns to the perinatal.[56]

^Wilber: "Are the mystics and sages insane? Because they all tell variations on the same story, don't they? The story of awakening one morning and discovering you are one with the All, in a timeless and eternal and infinite fashion. Yes, maybe they are crazy, these divine fools. Maybe they are mumbling idiots in the face of the Abyss. Maybe they need a nice, understanding therapist. Yes, I'm sure that would help. But then, I wonder. Maybe the evolutionary sequence really is from matter to body to mind to soul to spirit, each transcending and including, each with a greater depth and greater consciousness and wider embrace. And in the highest reaches of evolution, maybe, just maybe, an individual's consciousness does indeed touch infinity—a total embrace of the entire Kosmos—a Kosmic consciousness that is Spirit awakened to its own true nature. It's at least plausible. And tell me: is that story, sung by mystics and sages the world over, any crazier than the scientific materialism story, which is that the entire sequence is a tale told by an idiot, full of sound and fury, signifying absolutely nothing? Listen very carefully: just which of those two stories actually sounds totally insane?"[18]

^Wilber: "I am not alone in seeing that chance and natural selection by themselves are not enough to account for the emergence that we see in evolution. Stuart Kaufman [sic] and many others have criticized mere change and natural selection as not adequate to account for this emergence (he sees the necessity of adding self-organization). Of course I understand that natural selection is not acting on mere randomness or chance—because natural selection saves previous selections, and this reduces dramatically the probability that higher, adequate forms will emerge. But even that is not enough, in my opinion, to account for the remarkable emergence of some of the extraordinarily complex forms that nature has produced. After all, from the big bang and dirt to the poems of William Shakespeare is quite a distance, and many philosophers of science agree that mere chance and selection are just not adequate to account for these remarkable emergences. The universe is slightly tilted toward self-organizing processes, and these processes—as Prigogine was the first to elaborate—escape present-level turmoil by jumping to higher levels of self-organization, and I see that "pressure" as operating throughout the physiosphere, the biosphere, and the noosphere. And that is what I metaphorically mean when I use the example of a wing (or elsewhere, the example of an eyeball) to indicate the remarkableness of increasing emergence. But I don't mean that as a specific model or actual example of how biological emergence works! Natural selection carries forth previous individual mutations—but again that just isn't enough to account for creative emergence (or what Whitehead called "the creative advance into novelty," which, according to Whitehead, is the fundamental nature of this manifest universe)."[27]

^This interpretation is at odds with structural stage theory, which posits an overall follow-up of stages, instead of variations over several domains.

^This too is at odds with structural stage theory, but in line with Wilber's philosophical idealism, which sees the phenomenal world as a concretisation, or immanation, of a "higher," transcendental reality, which can be "realized" in "religious experience."

^The Madhyamaka two truths doctrine discerns two epistemological truths, namely conventional and ultimate. Conventional truth is the truth of phenomenal appearances and causal relations, our daily common-sense world. Ultimate truth is the recognition that no-"thing" exists inherently; every-"thing" is empty, sunyata of an unchanging "essence". It also means that there is no unchanging transcendental reality underlying phenomenal existence. "Formless awareness" belongs to another strand of Indian thinking, namely Advaita and Buddha-nature, which are ontological approaches, and do posit such a transcendental, unchanging reality, namely "awareness" or "consciousness." Wilber seems to be mixing, or confusing, these two different approaches freely, in his attempt to integrate "everything" into one conceptual scheme.

^The perennial position is "largely dismissed by scholars",[16] but "has lost none of its popularity".[17] Mainstream academia favor a constructivist approach, which is rejected by Wilber as a dangerous relativism. See also Perennialism versus constructionism.

^"I have not identified myself with the perennial philosophy in over fifteen years ... Many of the enduring perennial philosophers—such as Nagarjuna—were already using postmetaphysical methods, which is why their insights are still quite valid. But the vast majority of perennial philosophers were caught in metaphysical, not critical, thought, which is why I reject their methods almost entirely, and accept their conclusions only to the extent they can be reconstructed""Archived copy". Archived from the original on 2006-03-22. Retrieved 2006-03-14.CS1 maint: Archived copy as title (link)

... Ken has produced an extraordinary work of highly creative synthesis of data drawn from a vast variety of areas and disciplines ... His knowledge of the literature is truly encyclopedic, his analytical mind systematic and incisive, and the clarity of his logic remarkable. The impressive scope, comprehensive nature, and intellectual rigor of Ken's work have helped to make it a widely acclaimed and highly influential theory of transpersonal psychology.

Joseph Vrinte, Perennial Quest for a Psychology with a Soul: An inquiry into the relevance of Sri Aurobindo's metaphysical yoga psychology in the context of Ken Wilber's integral psychology, Motilal Banarsidass, 2002, ISBN81-208-1932-2